Abrasive equipment



SePt- 2, 1941- v. M|N|H 2,254,234

ABRASIVE EQUIPMENT A Original Filled Oct. 9, 1933 y ATTORNEYS vPatented Sept. 2, 1941 ABBASIVE EQUIPMENT r Verne E. Minich, Scarsdala-N. Y., assigner to The American Foundry Equipment Company, Mishawaka, Ind., a corporation of Delaware Application October 9, 1933, Serial No. 692,743

' Renewed April 7, 1989 4 Claims.

This invention relatesxto abrasive equipment and more particularly to apparatus .for cleaning metal sheets, castings and the like by impinging the abrasive. particles at a blasting velocity against the article to be cleaned.

According to this invention the machine is so constructed and arranged as-to throw or hurl particles of abrasive in a predetermined direction and over a predetermined area at a blasting velocity. The use of compressed air as required in conventional systems with accompanying cumbersome and expensive compressor apparatus is eliminated. The machine comprises generally a rotor including a disc which may be removably mounted on the end of a rotatably mounted drive shaft. Radially arranged blades project laterally from one side of the disc. The blades are of limited length extending inwardly from the disc periphery preferably not more than one-half of the disc radius.

The abrasive is fed on to a stationary inclined chute having an off-center discharge outlet which feeds the abrasive by gravity forced feed, or otherwise, into the path of the moving blades.

The chute may be adjustably secured to a stationary closure disc positioned opposite the 'blade carrying disc above mentioned. A uniform regulated supply of abrasive is fed intothe upper end of the feed chute. The abrasive slides by the action of gravity down the feed chute and shoots off the oil-center discharge outlet of the chute directly into the path of the moving blades. The o-center discharge end of the feed chute is positioned adjacent the inner end of the moving blades. Each successive blade, as it reaches the discharge end of the feed chute, picks up a regulated amount of the abrasive particles moving outward between the blades, changes the direction of movement of the particles into approximately the direction of the moving blades. the blades operating to throw the abrasive at blasting velocity in a predetermined direction.

By feeding the abrasive into the path of the moving blades lin an oi-center position with respect to the rotating radius of the blades, directional control of the thrown abrasive is accomplished. The abrasive can thus be thrown over a predetermined area s o as to do useful work.

An object of this invention is to provide an abrasive blast machine so constructed as to permit directional control to the abrasive thrown therefrom. l

Another object of this invention'is to provide an abrasive blast machine provided with means direction and over a predetermined area whence the flying abrasive about the machine not directionally controlled and doing useful work, 'is substantially eliminated.

Another object of this invention is to provide an abrasive blast machine which comprises few.

moving parts, which' is simple in connection, which can be economically made and assembled, which has a low power consumption for the work done, which imparts to the abrasive particles a highly eiective abrasive velocity, which causes a minimum disintegration of the abrasive particles, which operates in such a manner as to reduce thewear of the abrasive particles on the various parts of the machine to a. minimum, which occupies a small space area, and which is highly adaptable for the cleaning of metal sheets, castings, forgings, metal parts and other articles.

Other objects of this invention will become apparent as the disclosure proceeds.

In order that .a clearer understanding of my invention may be had, attention is hereby directed to the accompanying drawing, forming part of this application and illustrating certain possible embodiments of my invention.

Referring to the drawing:

Fig. 1 is a face view of the abrasive blast machine with abrasive particles being shown fed intolthe machine and thrown therefrom, certain parts being broken away to more clearly illustrate the construction;

Fig. 2 is a vertical cross sectional view through the machine, this view being taken on line 2 2 the shaft 5 is removably attached to the disc member i by means of the removable bolts l.

A plurality of uniformly spaced blades 3 laterally project from the side of the disc member i adjacent the periphery thereof. The blades 3, .may be cast integral with the disc member i or they may be .detachably secured thereto by means of removable bolts or other suitable means ior throwing abrasive in a definite predetermined as desired. The blades are preferably radially arranged with respect to the rotating axis oi' the disc member I, although they may be, if desired, slightly inclined forwardly with respect to the rotating radius of the disc. 'I'he blades are of limited length and extend inwardly only a fraction of the disc so as to provide a central space within which a feed chute may be positioned.

- A continuous metal ring 23 connects the blades together in rigid fixed assembly. The central space dened by the inner end of the blades 3 may be closed by means of a stationary disc 8 adjustably mounted on the stud 21 extending inwardly from the horizontal frame member 9 mounted on the supporting frame members I I.

The inclined feed chute comprising a bottom wall 2 and side walls 20 is positioned within the central space defined by the rotatably mounted blades 3 and positioned between the rotatable disc member I and the stationary disc member 8. The feed chute is adjustably and removably attached to the stationary disc member 8 by means of bolts or screws 2|, which extend through the adjusting slots 28 provided in the disc 8. The distance between the discharge end of the feed chute and the blade 3 can thus be regulated and adjusted. Likewise, the point at which the abrasive is fed onto the advancing faces of the blades can be adjusted by rotating the disc 8, carrying the feed chute, to the desired location. 'Ihe disc 8 may be fixed in any desired position by manipulating the nut 29 carried by the stud 30 projecting through the slot 3i provided in the disc 8, as clearly shown in Fig. 1. It is understood that any convenient means, other than that shown, may be used for adjusting the feed chute with respect to the throwing blades. The direction of discharge of the abrasive from the rotor can thus be varied as desired.

An opening is cut through the stationary disk 8 and one of the side walls 20 of the chute member to receive the discharge end I3 of a feed pipe I2 through which abrasive is fed into the feed chute. 'I'he feed pipe is adjustably supported by means of a bracket I l, one end of which is secured to the feed pipe and the other end adjustably secured to the horizontal frame member 9. The feed chute 2 is stationary during the operation of the machine but is preferably so arranged as to permit the adjustment of the disr charge end thereof with respect to the moving blades 3. v

A regulated supply of abrasive is fed from the pipe I2 to the upper end of the feed chute 2. The abrasive a slides downwardly under the action of gravity, forced feed or other means along the smooth bottom of the feed chute and as it leaves the discharge end of the feed chute, it shoots outwardly into the path of the moving blades 3, as shown more particularly in Fig. 1. 'Ihe particles are caught by the moving blade 3 advancing at a great speed and the direction of the moving particles changed to substantially the direction of the moving blade. As the blade advances further, the particles deposited thereon are thrown centrifugally from the rotating blade in a predetermined direction. The abrasive particles are carried by the moving blade approxiin Fig. 1, substantially all the abrasive is tangentially thrown or discharged from the machine over approximately a angle and there is 1ittle uncontrolled abrasive iiying from the machine around the remaining portion of the wheel. A directional control of the abrasive is thus substantially accomplished. i The breadth of the path swept by the abrasive is determined by the distance between the discharge end of the disc member I and the discharge end of the ring member 23. The length of the abraded area is determined by the size of the rotor, the length of the blades and the distance of the rotor from the work. The work should not be too far removed from the wheel, however, since the effective abrasive velocity of the particles would be reduced by the air friction.

To prevent any of the particles of abrasive from falling inwardly into the machine, an abrasive bafile plate or secondary lip member 22 is provided which is positioned underneath the discharge end of the chute. The secondary lip 22 carries a gasket 25 of iiexible wear resisting material, such as rubber, the end of which is adapted to contact the inner end of the moving blades. Should any of the abrasive particles discharged from the feed chute 2 fall inwardly so that they would be beyond the reach of the inner end of the blades 3, the secondary lip 22 and associated gasket 25 operates to deposit the particles within the path of the following blade. Particles of abrasive are thereby effectively prevented from falling into the rotor Where they would produce undesirable operating friction and wear on the various parts of the machine.

'Ihe machine as above described, when driven by a ten horsepower motor, is able to eiiiciently and effectively clean a sheet area approximately two and one-half feet wide and nine feet long per minute, as compared with a sheet area two 'and one-half feet wide and three feet long per minute by means of the conventional system using compressed air, which further requires a driving motor of one hundred horsepower or more. The

7 conventional system also requires expensive air compressor equipment, such as compressor engines, tanks, piping and valves. This equipment is expensive to operate and keep in repair and the moving abrasive quickly wears out the air nozzles, valves and piping. In the present airless abrasive blast machine the moving particles have little opportunity to contact the parts of the machine after they have been given an abrasive velocity. Y

The direction in which the abrasive is thrown may be regulated by adjusting the discharge end of the feed chute with respect to the moving b1ades,the abrasive discharge being fired from approximately one-fourth of the wheel circumference under normal operating conditions of 2250 revolutions per minute. The area of discharge, however, will vary within a narrow range. depending upon the rotating speed of the machine, the length of the blades, and theposition of the discharge outlet of the feed chute.

The machine is adapted for a variety of different uses, such as the cleaning of metal sheets, castings and other articles. The machine may be mounted upon any suitable standard or may be associated with other apparatus, such as a tumbling mill. 'I'he machine is made of few parts, and may be inexpensively manufactured and assembled. It is furthermore, strong and durable in' construction, safe and substantially foolproof in operation, requires little iioor space, and is highly eilicient.

AWhile certain novel features of the invention have been disclosed and are pointed out in the annexed claims, it will be understood that Various omissions, substitutions and changes may be made by those skilled in the art without departing from the spirit of the invention.

What is claimed is:

1. An abrasive machine comprising a rotatably mounted member, a plurality of radially extending blades peripherally positioned around said member, a feed chute for conducting the abrasive on to said blades, and a lip portion positioned below and extending from the end of said chute operative to collect the abrasive particles tending to fall inwardly into the machine and deposit the same on to the moving throwing blades.

2.,An abrasive machine comprising a normally stationary feed chute, blades rotatably mounted about said feed chute for throwing the abrasive as vit leaves the chute, said chute comprising a bottom wall, side walls and a lip portion positioned below said bottom wall and operative to collect the abrasive particles tending to fall inwardly into the machine and deposit the same in the path of saidrotating throwing blades.

3. In a centrifugal abrading apparatus, a drive shaft mounted to rotate in a substantially horizontal plane at high speed, a 'head structure mounted on said shaft to rotate in a substantially vertical plane, said head structure having a pliuality of abrasive throwing blades extending inwardly short of the axis of rotation of said head structure to provide a central space, means for concentrating the abrasive thrown by said abrasive propelling blades in a generally downward direction, said means including a normally stationary downwardly inclined feed chute positioned within said central space having' its lower end terminating closely adjacent the path of rotation of the inner ends of said blades and above the horizontal plane extending through the axis of rotation of said head structure, and means for supplying abrasive to the outer facing surface of said chute at approximately the twelve oclock position.

- 4. In a centrifugal abrading apparatus, a drive 4shaft mounted to rotate in a substantially horizontal plane at -high speed, a head structure mounted on said shaft to rotate in a substanl tially vertical plane, said head structure having a plurality of abrasive throwing blades extending inwardly short of the axis of rotation of said head structure to provide a central space, means for concentrating the brasive thrown by .said abrasive propelling blades in a generally. downward direction, said means including a normally stationary downwardly inclined feed chute adapted to conduct abrasive on the outer facing surface thereof positioned within said central space having its lower end terminating closely adjacent the path of rotation of the inner ends of said blades and abovethe horizontal plane extending through the axis of rotation of said head structure, means for supplying abrasive to the outer facing surface of said chute at approximately the twelve oclock position, and an abrasive deiiector element extending from the lower end of said feed chute downwardly for preventing inward deflection of the abrasive discharged from the lower end of said chute.

VERNE E. MINICH. 

